


A Freak

by orphan_account



Category: Undertale (Video Game)
Genre: Body Worship, Cunnilingus, Dark, Dominant Reader, Eventual Smut, F/M, Gender-Neutral Pronouns, Hate Sex, Mind Break, No Romance, Other, Power Play, Reader Is Not Chara (Undertale), Reader Is Not Frisk (Undertale), Reader has a coohie, Sorry Not Sorry, Undertale Genocide Route, Yandere, idk what else to tag, just an all around good bad time, submissive sans
Language: English
Status: In-Progress
Published: 2019-06-18
Updated: 2019-06-19
Packaged: 2020-05-14 02:37:39
Rating: Explicit
Warnings: Graphic Depictions Of Violence, Major Character Death, Rape/Non-Con
Chapters: 2
Words: 4,034
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/19264240
Author URL: https://archiveofourown.org/users/orphan_account/pseuds/orphan_account
Summary: The human tries something new that throws Sans completely off guard.Dark fic.





	1. Thinking outside the box

That look.

That look on their face was something different. The human look like a mess,an absolute wreck, like they had been through the wringer a hundred times. However, to his shock despite this, despite fact they had fought countless times before this, that look was something different. Something disturbing that would make a stomach turn.

It was one of confidence.

Knowing.

Victorious.

Determination of course but most importantly….

It was one of pure unrestricted sadism.

The human knew the outcome of this battle from the very start.

How to win it because…

"..... You're really kind of a freak huh?"

They had already won before.

It was evident even before the human dodged his strongest attack at the start. And his fate was sealed when it repeated for all the others. The human moved with ease, escaping his bones as if they were nothing. Not a single hit landed on them, the damn thing even had the gall to laugh, narrating childishly as they moved like it were some game.

It frustrated Sans to end.

His friends… his family… Papyrus… they were all just toys for this human to play with and discard at their leisure. They had no remorse, not even when the human teased their victims of knowledge they would never know lest they, in a past life, were friends with monsters. That just made the whole situation even sicker. To have someone love and care for you, to achieve the ultimate good ending for everyone, just to follow down this genocidal path.

Sans wondered what was the point of it all. Why was he still fighting this human that saw him nothing more as a high score to be beat. Nothing he was throwing at them was landing, from his bone attacks, the blasters, and even throwing their soul from wall to wall.

It was hopeless.

So hopeless.

And yet, he went on.

Now it was the final straw. No holding back, he'd launch every attack he had in the book at this human's way. The circle of blasters fired around the soul, Sans thought he almost had them by how much the human had to thread the needle to narrowly escape being vaporized but in the end…

In the end, it wasn't enough.

He was tired.

Disheartened.

Many things. Sans wasn't a crying man, Papyrus did that enough for the both of them, but boy oh boy was it getting close.

"Well… I guess that's it then." He shrugged, sweat falling down against his skull.

"Just. Make it quick, kid. I'm dying to meet up with Papyrus after this." He closed his eyes, chuckling bittersweetly. Sans already knew the human would just skip his turn and kill him. It was only just a matter of time. He could already hear the humans soul move the box that entrapped their heart on the battlefield.

You know, it's funny how only human souls would be subjugated to having bullets throw their way while trapped in a small box Sans thought. In battles like this, it made it nearly impossible for humans to escape unless a monster offered them mercy or killed them. With his teleportation ability Sans could easily escape the human, save himself, but what kinda world would he want to live in with this human running rampage. What kinda world would he want to live in without his little bro.

....

...

.

Sure was taking the human a while to inch their box over to the FIGHT option, huh?

Had they forgotten how?

Sans opened an eye socket and was surprised to see the human hadn't moved their box from the field to their attack button.

Rather, the human had brought it over to _him._

Now that…

That face.

That was a face Sans had never seen before.

And it frightened him to the very core of his would.

The skeleton man tried to take a step back. Emphasis on "tried". He found that his back hit against an invisible wall that lined up with the area the box took up. And even more than that the human was close to him. Dangerously close to him, their bodies nearly touching. It was suffocating.

"Ah, a little too close kid." He said. No matter which side he stepped toward, the human followed. He didn't like it. He didn't like it at all.

"Yeeeah, imma, just…" he tried to teleport behind the human, aiming several feet away close to the door but, again, he found himself hitting a wall.

This time face first.

The skeleton rubbed at his dome, confused. "The hell…? What, what did you do to me-"

When Sans turned around the human had an excited look on their face, practically dancing in their spot. "Yes, yes, yes! Oh, I hoped it would work."

"What worked?" Sans asked, utterly confused as he tried, again and again, to teleport himself out of this invisible cage.

"It took a little coding, but I was able to increase the field range of where I could move the bullet box." They said as a matter of factly, clearly amused at Sans trying to escape. "I thought I would break the game when doing this, thought it wouldn't work on monsters the same as humans, but I proved my theories wrong."

"What are you even talking about?" Sans couldn't understand what was happening. Why couldn't he leave? Why were his powers not working?

"You're probably wondering why you're stuck here, right?" Sans rested his back against the wall, sweating at how much magic he was feebly spending trying to get out. Even though his smile was a permanent fixture on his face, he was fearful down to his bones. "That's because we're still in "battle". You can't leave, and neither can I unless one of us spares the other, or dies. But…"

A wicked grin appeared on their face."The former isn't really an option, is it?"

"Look kid-"

"Stop calling me kid, Sans, I'm an adult. Old enough to drink at Grillbys for Christ's sake." The human rolled their eyes.

"whatever," Sans scoffed. " if you're gonna kill me, then just do it already." Sans didn't fear death, he welcomed it. Just, whatever this was is what terrified him. The bucket of bones could predict anything, read people like a book, but right now he was going in blind and he hated every second of it.

"I'm not going to kill you" Sans stared inquisitively as the humans drew closer with each methodical step. They had pocketed the knife to their shorts back pocket and… Wait was that blush sweeping across their face? His question was answered as the human's sweater was practically touching the skeletons white and he could see everything up close and personal. The human's breath was right up against sans check bone as they whispered, "not yet that is."

San's bones began to rattle and the human giggled at this. They slide their hand underneath his shirt, gently stroking at his spinal cord and cooing into where ears would be. "Shh shhh shhh… don't be scared Sansy. You'll only make this harder for yourself."

Without a second thought, San's eye went up in blue flames once more. He shoved the human off of him and launched a bone straight into their shoulder.

Sans was sloppy for he was aiming for their heart.

This did not amuse the human. Not one bit. They reached for their shoulder and yanked the attack out of their body. It had only done maybe 10 damage, maybe 15 since it threw them off guard and the KR poison acted fast, but they were still in good health stat wise. Still, a dark look appeared on their face.

"I wouldn't try that again if I were you." It was phrased as a suggestion but it was really a command.

"Or what?" Sans said as he pulled his shirt down. This was clearly new ground for the human as well, seeing as they weren't able to dodge his attack.

"Because."

"Because what?

"Beeecause," and within a second they closed the already tight gap between the two of them. The human was taller than him.

And even more so as he coward underneath them, his knees buckling from the sheer pressure the human exuded.

"Because if you don't fucking play along, I will just come back to try it again until you do. Both you and I know how determined I am to get what I want." The human dug their face into the Skeleton's neck, kissing and licking at the bone fervently as their hand once again fished for under the monster's shirt.

"And [Y/N] isn't going to stop until…"

You slashed at San's shorts, ripping them to one side.

"You…"

Your other hand cupped at between his pelvis.

"Give me…"

Your hand rubbed at the bone, blue magic beginning to form, betraying the skeletons body as genitalia formed.

" **What I want.** "


	2. Won't You Smile For Me?

Sans’s eyes were pitch black. Had… had you really proposed that you two were going to have sex? It would be of been funny, a real sick joke to play on him, had it not been for the way your hand was aggressively trying to get his dick to summon. It was uncomfortable, way to fast to be enjoyable and it hurt. He didn’t move though. His whole body remained stiff in shock for those moments as you tried to get him hard.

 

“heh….” he finally said. It was so low you barely heard it. You stared down at him, wondering what that sound was supposed to mean. “ paps was wrong, about you. no one and nothing can save your soul. y o u ’r e  r o t t e n t o t h e c o r e.”

 

That statement.

 

That statement turned you on so hard.

 

You stopped what you were doing, pulled him by the shirt up to your face and smashed your lips against his lips. Sans just let it happen, limp as a doll. Like he was just your little unresponsive sex toy to do with as you pleased. You broke the “kiss”, breathing heavily as you stared into the skeleton’s vacant eyes. You were a mess. An absolute disaster to look at with your face practically on fire, and hands shaking from the pure high of the excitement.

 

“That's.” You managed to get out after a few seconds of intensity. Your smile was sweet, almost loving before the skeleton. With each step forward you took the invisible cage moved with till San’s back was against one of the pillars. “That is what I love about you Sans. You see me for what I really am.”

 

“....a demon?”

 

Your eyes went wild and you slammed the knife against the pillar. A few more inches to the left, and you would have stabbed the man right in the eye.

 

“ **Yes.** ”

 

And with that, you were back to kissing him. Mouth crushing against his teeth, your tongue lapping at his perpetually grinning teeth. Your hands went back to below his waist, pumping at his flaccid erection.

 

You did as you pleased.

 

And Sans just let it happen.

 

You’d think he was dead from how everything but his cock was stiff. Sans meanwhile was thinking. Thinking about how in the Underground it all came to this: being sexually assaulted in the grand hallway before Asgore’s throne room. He thought about killing the human right then and there or calling for Asgore’s help. Something. Anything to stop this from happening. This whole thing was bad.

 

It was wrong.

He didn’t want this.

 

No.

 

No no no nonononononO.

 

….

 

But what else could he do?

 

There was no other way out of this. If Sans killed you, you’d just come back to try again and again till it worked in your favor. Because that was just the kind of person you were. The kind of person to never quit till you got what you want, even if you had absolutely nothing to gain by the end of it. The world could end, thousands of monsters could perish and you’d see it nothing more as an achievement. All because of that, your DETERMINATION, you could play God and live your life as if it were just a game behind a screen. _heh... determination is a hell of a thing, eh, Gaster?_

 

There was no use hiding from it. You had become too powerful, the way you smelled of dust and with ease mercilessly killed all those monsters without even a second thought. Not a single soul, young or old you tried to spare. You couldn't even be considered a human anymore, no.

 

You truly were a demon.

 

And Sans was about to make a deal with a devil.

 

He granted you permission to enter his mouth, a blue luminescent tongue poking out to entangle itself with yours. Sans grabbed at you your waist and grinded it again your mound, hard. This surprise you, you had expected him to just take it lifelessly. You thought Sans would be too lazy, too apathetic from all you’d done to even entertain the thought of having sex with you. But instead, he was reciprocating. This made you smile.

 

“don’t take this the wrong way, [Y/N].” He grabbed a hold of your hair, ripping your head away from his mouth causing you to hiss in pain. Once again the flame that you oh so loved about him ignited a new.“ i’m not doing this because i’m enjoying it. the thought of fucking you makes my figurative skin crawl.”

 

“That bulge says another thing, I’d say.” you managed to retort, eyes glancing down between both of your legs. His once limp cock was now rising, poking at your crotch. He shook his head.

 

“ i just ain’t gonna go down on ya without a FIGHT.”

 

That wicked smile of yours returned on your face

 

“ **Good.** ”

 

Within an instance he teleported the both of you, switching places with the other. Now it was you who was pressed up against the pillar and having your shorts ripped off from your bottom. Your hands went to work again, helping Sans shrugged off his hoodie as your mouths clashed against each other in rough tongue action. Once it was off you arms wrapped themselves around San’s neck to bring your faces closer together as if any distance from your already merged bodies was too much to bare. His mouth tasted like ketchup but you didn’t care if it tasted like mustard or honey. To you, the victory of being able to experience this was gold like the flowers you fell upon those hours ago.

 

You sighed in ecstasy as his tongue moved down to your neck, lapping at the sensitive skin. Sans could easily rip out your throat, but the fact that nothing more that came from his kisses were nibbles and superficial hickeys meant the world to you in that moment. It showed how much power you had for him still, even in this submissive act.

 

Sans knew this.

 

And he hated it to no end.

 

So when his tongue wandered down to the wound he had caused earlier his disobedience would not go overlooked.

 

You hissed out in pain, and not the kind you’d enjoyed, grabbed his neck and collided foreheads with him. That dark look was back on your face only this time it was _pissed._

 

“ Don’t get cheeky with me, bonehead.” Your voice was threatening. Your grip was murderous and tight. With your free hand, you dislodged the knife from the pillar and pointed it at Sans’s heart. “ **Try that shit again I’ll reset this world till the next Sans does.** ”

 

Enduring the hellish 8-minute battle leading up to this be damned. You had already perfected your skills to evade the scripted attacks Sans would throw at you. A simple reset meant not to you, but everything to Sans. The skeleton didn’t want to object any of the other hims, or anyone else for that matter to being raped.

 

So, for the sake of the other timelines, Sans would bear this burden in the hopes that no other monster would have to live through this, in their final moments while their world was still intact.

 

“....okay.” he muttered begrudgingly You just stared at him, displeased by the response till he spoke up again. Sans turned his head, too proud to meet your eyes as he said, “ sorry.”

 

“I don't you to tell me you’re sorry,” you barked, letting go of his neck and retracting the knife so you could rudely shove him down to his knees. For a moment he was confused till he saw you remove what was left of your shorts. A chill ran down his spine as you propped your leg on his shoulder. You demanded him to,“ Show me your apology, bitch.”

 

Sans’s gaze moved from yours and down do your loins. Despite the little stunt he had pulled you were still pretty wet down. He just stared at it, stunned at what to do next. A bony hand only made it halfway before you swatted it away. “Use your fucking mouth, Smiley Trash bag, I don’t want your phalanges cutting my shit up down there.”

 

“not much of a masochist are ya, [Y/N]?” He tried to lighten the mood with a joke. Even now he couldn’t help but quip at you.

 

“Not when your bones are almost as sharp as a dusty knife,” you smirked before getting a hold of the back of his head and pushing it against your mound.  He read the hint. He read it loud and clear and got to work to making it up to you.

 

His blue tongue creeped out, hesitantly, Sans’s face was flushed with blue. He stared at your aching crotch for a moment. It was too embarrassing for him to say he had never gone down on another monster before. Hell, he had never slept with anyone before this at that. Skeletons like he and Papyrus had fairly nonexistent libidos, practically making them asexual. It didn’t help that Sans was too lazy to even jack himself off when the occasion arised. He always imagined he’d lose it to a partner he actually liked, maybe even loved, like that lady behind the door to the ruins even if he ever got to meet her. But that wasn’t the case now was it?

 

Sensing your impatience, he gave tentative lick at your pussy, looking up for your approval. Your tense gaze softened and you’d pet at his smooth bald head. You cooed softly,

 

“ A virgin. Just like your brother.”

 

Sans nearly shot up to his feet had his face come to a screeching halt halfway up your body before being met eye to eye with the knife. “ Ah, ah, ah. What did I just say, Sansy? **Another disobedience like that and I’m resetting this whole fucking world and I mean it.** ”

 

Sans was glaring daggers at you. Mentioning his brother, implying that… that… !!

 

“Relax,” you sighed, stroking the side of his skull. “In another timeline, it was all consensual. Sweet even. I never suspected your brother for the type to fuck on the first date but a little flirting can go a long way.”

 

You were just provoking him at this point, testing to see if he’d try something again. Oh, how the look on his face was simply delicious to you. _So much anger and still you smile through it, Sans._ how you longed to see his face cave in and curl in disgust over yourself, but you got the feeling you were getting close.

 

Without much of a choice, Sans continued his cunnilingus. He may have been inexperienced, but he was a fast learner. It was another thing that you loved about him. Despite his lazy demeanor, Sans was actually quite intelligent. His tongue burrowed pass your folds and into the opening. The appendage dug around your pussy, stretching its walls as he got to work pleasuring you. It was messy at first, a little painful but he read your reactions easily and tried something new. Since his tongue was made of magic, he could manipulate its length and girth a bit as he face fucked your insides. Soon he got the rhythm of it and you began to moan little by little the better he got. Every now and again she would swipe at your good spot that would cause your back to arch against the pillar.

 

“Mmm… Yeah, Sans, right there, right there.” Your hand moved from his head and under your sweater to play with your breasts, the other dropping the knife to rub at your aching clit as your legs wobbled to keep you standing. Sans noticed this. No not the fact you dropped the knife, he knew just as well with his low HP value all it would take is a strike with the intent to kill from your bare hands to end him. He noticed the fact that all this intense pleasure was making your knees weak and any second they would give out. The skeleton removed his tongue from your sopping wetness to propped your other leg up on his shoulder and you opened an eye to see if he was going to try something stupid again. He was not. Instead, once both your legs were on his shoulders, his hands wrapped themselves around your back. Cradling you delicately as he laid you to rest on his long-forgotten hoodie. It was almost romantic at how hard he was trying to make sure you didn’t fall flat to the floor. You were almost grateful, blushing at this fact.

 

Once you were comfortable as one could be on the floor, he spread your legs and returned to eating you out. Your fist grasped and balled up the fabric of his hoodie as he targeted at your g-spot. He was relentless in his attacks on your spot. It was deep, deep in there but he had found it at last and he wasn’t going to lap right past it anymore. Your moans echoed throughout the hall, it was all Sans could hear.

 

All he could want to listen to.

 

This whole situation was wrong. Nothing like he had expected to lose his virginity to. He didn’t love you, but, maybe, just as you pretend to be human he could pretend that he loved you just the same. His life was over, so why not try to enjoy it too, even at the cost of his sanity. He’d gladly give that over to you to just escape the reality. It was a good thing skeletons didn’t need to come up for breath, because you were about to explode.

 

Your climax came and it covered his mouth. You tasted oddly sweet for such a rotten creature, Sans thought. You gently pushed Sans’s face away from the oversensitive ache of your crotch so you could recollect yourself from the high. Sans did as such and even though he didn’t have lungs, he found himself panting from the sheer exercise of it all along with you. Your submissive looked back up at you expectantly.

 

“Mmmm, good boy.” You praised him, beckoning him to crawl up to you to give him a kiss. He now tasted like the both of you, ketchup and all and that made your heart flutter. Wrapping your arms around him you planted kiss after kiss all over his skull, congratulating him on a job well done as he laid his face on your chest. “ So good. Very good.”

 

“... better than Papyrus?”

 

This.

 

This surprise you. He had lifted his face off from your chest and you could see it there.

 

A frown.

 

The false impression of happiness was gone from his face.

 

You did it. You broke him. _No one else would ever get to see this expression complete and utter defeat on his face other than me._

 

“Yes, Sansy.” You caressed the side of his glowing face with the back of your hand, your knuckles flowing down the single stream of tears that fell along his skull.

“Even better than Papyrus.”

 

He smiled again.

 

Only this time.

 

It would be his last.

**Notes for the Chapter:**

> I was worried this would turn into too much of a power struggle, hot as that is, but I think I pulled through in the end!
> 
> Love you, Sans. In this timeline and the next ♥

**Author's Note:**

> Yeah Uuuuh let me know if people want me to write the actual sex scene. Ill probs have reader be dfab for the next chapter but if there's interest in a dmab ill make the third chapter a version with that one.
> 
> I love Sans also ! Don't take this fic as me hating him he's one of my favorite UT characters.


End file.
